Methods of forming building wall systems and building wall systems

ABSTRACT

A method of forming a building wall system in the absence of building paper or housewrap that comprises providing a generally flat structural insulating sheathing. The sheathing comprises at least a first layer, a second layer and a third layer. The first and third layers comprises an alkenyl aromatic polymer foam. The second layer comprises paperboard. The insulating sheathing is fastened to the stud wall to form the building wall system such that a seal is formed that inhibits water from penetrating therethrough. The building wall system in the absence of building paper or housewrap passes the test requirements set forth in Section 1403.2 of the 2003 International Building Code.

FIELD OF INVENTION

The present invention is directed to methods of forming a building wall system and building wall systems. More particularly, the present invention relates to methods of making a building wall system and building wall systems that comprise at least three layers and are resistant to rain penetration.

BACKGROUND OF THE INVENTION

Insulating material is used in the construction of buildings. Popular modem-day insulating materials include foam boards that are often manufactured from a polystyrene polymer having a laminated outer coating or facer. The foamed polystyrene boards have insulating properties associated therewith. The laminated coating functions primarily to protect the foamed polystyrene polymer and provide the foam board with enhanced protection, durability, strength and resiliency.

To form a building wall system, such existing foamed polystyrene boards may be installed with a building paper or housewrap. The building paper or housewrap assists in preventing or inhibiting rain penetration. Building paper or housewrap is presently required if the exterior covering is not determined to be weather resistant (e.g., brick, stone, fiber, cement, and lapwood siding, vinyl siding, aluminum siding, or stucco).

It would be desirable to have a method of forming a building wall system and a building wall system itself that resists water penetration and does not necessitate building paper or housewrap, while still providing desirable properties.

SUMMARY OF THE INVENTION

According to one method, a building wall system is formed in the absence of building paper or housewrap. A generally flat structural insulating sheathing is provided that comprises at least a first layer, a second layer and a third layer. The first layer comprises an alkenyl aromatic polymer foam. The second layer comprises paperboard. The third layer comprises an alkenyl aromatic polymer foam. A stud wall is provided. The insulating sheathing is fastened to the stud wall to form the building wall system such that a seal is formed that inhibits water from penetrating therethrough. The building wall system in the absence of building paper or housewrap passes the test requirements set forth in Section 1403.2 of the 2003 International Building Code.

According to another method, a building wall system is formed in the absence of building paper or housewrap. A generally flat structural insulating sheathing is provided that comprises at least a first foam layer, a second layer and a third foam layer. The first foam layer comprises a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof. The second layer comprises paperboard. The third foam layer comprises a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof. A stud wall is provided. The insulating sheathing is fastened to the stud wall to form the building wall system such that a seal is formed that inhibits water from penetrating therethrough. The building wall system in the absence of building paper or housewrap passes the test requirements set forth in Section 1403.2 of the 2003 International Building Code.

According to one embodiment, a building wall system in the absence of building paper or housewrap, comprises a stud wall and a generally flat structural insulating sheathing. The generally flat structural insulating sheathing comprises at least a first layer, a second layer, and a third layer. The first layer comprises an alkenyl aromatic polymer foam. The second layer comprises paperboard. The third layer comprises an alkenyl aromatic polymer foam. The insulating sheathing is attached to the stud wall such that a seal is formed that inhibits water from penetrating therethrough. The building wall system in the absence of building paper or housewrap passes the test requirements set forth in Section 1403.2 of the 2003 International Building Code.

According to another embodiment, a building wall system in the absence of building paper or housewrap comprises a stud wall and a generally flat structural insulating sheathing. The generally flat structural insulating sheathing comprises at least a first layer, a second layer, and a third layer. The first layer comprises a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof. The second layer comprises paperboard. The third layer comprises a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof. The insulating sheathing is attached to the stud wall such that a seal is formed that inhibits water from penetrating therethrough. The building wall system in the absence of building paper or housewrap passes the test requirements set forth in Section 1403.2 of the 2003 International Building Code.

According to one embodiment, a structural insulating sheathing adapted to be used in a building wall system comprises a first layer, a second layer, and a third layer. The first layer comprises an alkenyl aromatic polymer foam. The second layer comprises paperboard. The third layer comprises an alkenyl aromatic polymer foam. The insulating sheathing has a flexural strength of at least 170 psi as measured in accordance with ASTM C 393, an R-value of at least 2.0 (ft²)(° F.)(hr)/(BTU) as measured in accordance with ASTM C 518.

According to another embodiment, a structural insulating sheathing adapted to be used in a building wall system comprises a first foam layer, a second layer, and a third foam layer. The first foam layer comprises a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof. The second layer comprises paperboard. The third foam layer comprises a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof. The insulating sheathing has a flexural strength of at least 170 psi as measured in accordance with ASTM C 393, an R-value of at least 2.0 (ft²)(° F.)(hr)/(BTU) as measured in accordance with ASTM C 518.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of structural insulating sheathing according to one embodiment.

FIG. 2 is a side view of structural insulating sheathing according to another embodiment.

FIG. 3 is a side view of structural insulating sheathing according to a further embodiment.

FIG. 4 is a perspective view of the structural insulating sheathing of FIG. 1 being attached to a stud wall using nails according to one embodiment.

FIG. 5 is an enlarged view of the generally circular shape FIG. 5 of FIG. 4.

FIG. 6 is a perspective view of the structural insulating sheathing of FIG. 1 being attached to a stud wall using staples according to one embodiment.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The present invention is directed to building wall systems and methods of forming building wall systems that are resistant to rain penetration. The present invention serves as an air filtration retardant, drainage plain, and eliminates the need for additional weather protection, such as building paper or housewrap, to protect against rain penetration. The present invention eliminates the cost associated with forming and installing the building paper or the housewrap.

Referring to FIG. 1, a generally flat structural insulating sheathing 10 according to one embodiment to be used in the building wall systems of the present invention is shown. The structural insulating sheathing 10 comprises a first layer 12, a second layer 14, and a third layer 16. The second layer 14 of FIG. 1 is located between the first layer 12 and third layer 16. It is contemplated that the insulating sheathing may include additional layers, such as described below in conjunction with FIGS. 2 and 3.

According to one embodiment, the first and third layers 12, 16 comprise an alkenyl aromatic polymer foam. The term “alkenyl aromatic polymer” as used herein includes polymers of aromatic hydrocarbon molecules that contain an aryl group joined to an olefinic group with only double bonds in the linear structure, such as styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-ethylstyrene, α-vinylxylene, α-chlorostyrene, α-bromostyrene, and vinyl toluene. Alkenyl aromatic polymers also include homopolymers of styrene (commonly referred to as polystyrene), copolymers of styrene and butadiene, and rubber-toughened polystyrene (commonly referred to as high impact polystyrene or HIPS). The alkenyl aromatic polymer may be an oriented polystyrene (OPS). Another example of an alkenyl aromatic polymer foam is an extruded polystyrene foam.

According to another embodiment, the first and third layers 12, 16 of the structural insulating sheathing 10 may be formed by extruded polyolefin foam resins. One example of an extruded polyolefin foam that may be used in forming the first and third layers is an extruded polypropylene foam. It is contemplated that the polyolefin resins may be used in combinations with the alkenyl aromatic polymer resins. It is also contemplated that other foamed materials such as polyisocyanurate, polyurethanes, and polyester may be used alone or in combinations with the polyolefins and alkenyl aromatic polymer foam resins.

It is contemplated that the first and third layers 12, 16 may be independently formed from different resins. The first and third layers 12, 16 of the structural insulating sheathing 10 may be formed by an extrusion process. It is contemplated that the first and third layers may be formed by other processes.

The thickness of each of the first and third layers 12, 16 is generally from about 0.1 to about 1 inch. More specifically, the thickness of each of the first and third layers 12, 16 is generally from about 0.20 to about 0.50 inch. The thicknesses of the first and third layers 12, 16 may be different.

The densities of the first and third layers 12, 16 are generally from about 1 to about 3 lbs/ft³ and, more specifically, from about 1.5 to about 2 lbs/ft³. To increase the permeation of the water vapor, it is contemplated that the first and third layers may be perforated.

The second layer 14 of the structural insulating sheathing 10 comprises paperboard. The term “paperboard” as used herein includes the broad classification of materials made from cellulosic fibers such as primarily wood pulp and recycled paper stock on board machines. The paperboard may be laminated paperboard that consists of a plurality of layers of paper adhesively secured to each other. Thus, the second layer 14 may be comprised of several layers that may be different.

The paperboard may be, for example, kraft paper, chipboard, fiberboard and linerboard. Kraft paper as used herein includes pulp, paper or paperboard produced from wood fibers using a sulfate process. Chipboard as used herein includes paperboard that has been made from recycled paper stock. Fiberboard as used herein includes containerboard and vulcanized fiberboard. The fiberboard may be made from a combination of chemical pulp and recycled stock. Fiberboard as used herein also includes defibrated wood formed under heat and pressure and without the use of adhesives. The paperboard may also be a combination of one or more of the following: laminated paperboard, kraft paper, chipboard, fiberboard and linerboard.

The thickness of the second layer 14 of the structural insulating sheathing 10 is generally from about 0.05 to about 0.25 inch and, more specifically, from about 0.07 to about 0.125 inch.

It is contemplated that additional layers may be used to form the insulating sheathings. It is contemplated that optional laminated surface coatings or facers may be added to the insulating sheathing. Examples of insulating sheathings with optional laminated surface coatings are shown in FIGS. 2 and 3. In FIG. 2, a structural insulating sheathing 30 includes an optional laminated surface coating or facer 18 adjacent to and attached to the first layer 12. The sheathing 30 also includes a second layer 14 and third layer 16 as described above. In FIG. 3, a structural insulating sheathing 40 includes two facers 18, 20 that are adjacent to and attached to the respective first and third layers 12, 16. The sheathing 40 also includes the second layer 14. Thus, as shown in FIGS. 2 and 3, one or two facers may be added to the first and/or the third layers 12, 16.

The optional laminated surface coatings or facers 18, 20 may be made of materials such as polyolefins, high impact polystyrenes (HIPS), polyester, metallized films, foils, or combinations thereof. Examples of polyolefins that may be used to form the facers include polypropylenes and polyethyelenes. One example of laminated surface coatings or facers is aluminum foil. It is contemplated that other materials may be used in forming the optional laminated surface coatings or facers.

The thickness of the optional laminated surface coatings or facers is generally from about 0.5 to about 3 mils and, more specifically, from about 0.7 to about 1 mil.

The first layer 12, the second layer 14, and the third layer 16 that form the structural insulating sheathing 10 may be attached by several methods. For example, these layers may be attached to each other using an adhesive such as polyvinyl acetate, polyurethane, polyvinyl alcohol, or combinations thereof. It is contemplated that other adhesives may be used in attaching these layers.

The optional laminated surface coatings or facers 18, 20 may be attached to the first and third layers 12, 16 by the use of an adhesive. Examples of suitable adhesives include ethylene vinyl acetate (EVA), a mixture of EVA in polyethylene, ethylene vinyl alcohol (EVOH), block copolymers comprising polymeric regions of styrene-rubber-styrene such as KRATON® made by Shell Chemical Company, and modified EVAs such as BYNEL® made by Dupont. Modified EVAs generally have indices from about 6.4 to about 25 g/10 min. as measured by ASTM D 1238 and densities from about 923 to about 947 kg/m³ as measured by ASTM D 1505. It is contemplated that other suitable adhesives may be used.

The structural insulating sheathing 10 is a generally flat board sheet that may be manufactured in a variety of sizes. Popular sizes in the housing market include a 4′×8′ flat board sheet (4 feet by 8 feet) and a 4′×9′ flat board sheet (4 feet by 9 feet).

According to one method, insulating sheathing is provided, such as depicted in FIG. 1 with structural insulating sheathing 10. The building wall system may be formed in the absence of building paper or housewrap. In forming the building wall system, an insulating sheathing and a stud wall are provided. In FIG. 4, for example, a building wall system 60 is depicted that includes the structural insulating sheathing 10, a stud wall 70, and fasteners (e.g., nails 80). The fasteners 80 attach the structural insulating sheathing 10 to the stud wall 70.

According to one embodiment, the stud wall is made of wood. The stud wall, however, may be made of metal. One specific example of a stud wall is a 2×4 wood stud. It is contemplated that other sized wall studs may be used. The insulating sheathing is fastened to the stud wall by, for example, nails, adhesive, or staples.

Nails are desirable because they improve the structural strength of the building wall system as measured by ASTM E 72-98 (Section 14 Racking Load). One example of a nail that may be used is a 1¾ inch long roof nail. Such a nail desirably penetrates the third layer 16 of the structural insulating sheathing 10 such that the head of the nail is located near or at the face of the second layer 14. It is desirable for the head of the nail to be resting securely against the face of the second layer 14. For example, the head of the nail may be positioned such that some of the foam is compressed between the nail and the face of the second layer 14. During the fastening, the structural insulating sheathing and more specifically the first layer 12 of the structural insulating sheathing 10 forms a tight seal (e.g., like using a gasket) against the studs to prevent or inhibit rain from penetrating therethrough. Although not necessary, it is desirable for the nail to be installed using a pneumatic nail gun to assist in properly placing the nail and improving the efficiency of the installation process.

The fastening of the structural insulating sheathing may be done by staples. In FIG. 6, for example, a building wall system 160 is depicted that includes the structural insulating sheathing 10, a stud wall 70, and fasteners (e.g., staples 180). The staples desirably penetrate the third layer 16 of the structural insulating sheathing 10 such that the crown of the staple is located near or at the face of the second layer 14. It is desirable for the crown of the staple to be resting securely against the face of the second layer 14. For example, the crown of the staple may be positioned such that some of the foam is compressed between the staple and the face of the second layer 14. During the fastening, the insulating sheathing and more specifically the first layer 12 of the structural insulating sheathing 10 forms a tight seal (e.g., like using a gasket) against the studs to prevent or inhibit rain from penetrating therethrough.

Staples are typically installed using a pneumatic staple gun to assist in properly placing the staple and improving the efficiency of the installation process. In one method, the staples are positioned generally perpendicular to the stud walls. The staples may be positioned in other locations with respect to the stud walls including being perpendicular to the stud walls. It is also desirable to position the staples such that the edges of the foam do not raise from the stud walls. The crown of the staples may vary in size but are generally from about 7/16 to about 1 inch. If the staples are positioned generally perpendicular or perpendicular to the stud walls, then the staples are generally smaller in size, such as 7/16″, to assist in ensuring that the staples are positioned into the stud walls. The depth of the staples are generally from about 1 to about 1¾ of an inch.

According to another embodiment, the insulating sheathing is attached to the stud wall using a general construction adhesive. Examples of general construction adhesives include, but are not limited to, acrylics, urethanes, and silicones.

Because of its rain penetration protection, the building wall systems eliminate the necessity to have additional weather protection such as building paper or housewrap. The building wall systems also eliminate the necessity to tape the joints formed between adjacent insulating sheathing boards. Thus, the methods of installing the building wall systems do not necessarily need building paper or housewrap, or taping or sealing the joints between adjacent insulating sheathing boards. It is contemplated, however, that such building paper or housewrap, or taping may be used.

The insulating sheathing may be used in the stud walls that form residential or commercial buildings. Additionally, the insulating sheathings may be used in new construction and in remodeling or retrofitting of existing structures. On a building, the insulating sheathings are typically covered by an exterior covering such as siding, brick, stucco, stone, and cement. The insulating sheathings may be used with exterior covering that are not determined to be weather resistant (e.g., brick, stone, fiber, cement, and lapwood siding, vinyl siding, aluminum siding, or stucco).

The methods of forming the building wall systems of the present invention pass the test requirements set forth in Section 1403.2 of the 2003 International Building Code entitled “Weather Protection.” Section 1403.2 of the 2003 International Building Code mentions and incorporates ASTM E-331. ASTM E331-00 is entitled “Standard Test Method for Water Penetration of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static Air Pressure Difference.”

The building wall system forms a weather-resistant barrier that protects the interior wall cavity from water intrusion by demonstrating resistance to a wind-driven rain at a minimum differential pressure of 6.24 lbs/ft² (0.297 kN/m²) for two hours in accordance with Section 1403.2 of the 2003 International Building Code. The minimum differential pressure of 6.24 lbs/ft² (0.297 kN/m²) correlates to a wind speed of about 50 miles per hour (mph).

The methods of forming the building wall systems provide desirable structural strength as measured in accordance with ASTM E 72-98 (Section 14 Racking Load). By having such desired structural strength, additional building materials such as corner plywood, corner OSB (oriented strand board), diagonal bracing, shear panels, and metal corner strapping are not needed. Thus, the corners in any such building wall systems remain better insulated because the insulating sheathing will be used instead of the above-discussed additional building material.

The structural insulating sheathing generally has a flexural strength greater than at least 170 psi and desirably greater than 225 psi in accordance with ASTM C 393. The structural insulating sheathing more typically has a flexural strength greater than at least 300 psi and desirably greater than 400 psi in accordance with ASTM C 393.

The generally flat structural insulating sheathing desirably has a permeability greater than 1 perm as measured in accordance with ASTM E 96. The R-value of the generally flat structural insulating sheathing is generally greater than about 2.0 (ft²)(° F.)(hr)/(BTU) as measured in accordance with ASTM C 518. It is contemplated that the R-value of the generally flat structural insulating sheathing may be greater than 2.5 or 3.0 (ft²)(° F.)(hr)/(BTU) as measured in accordance with ASTM C 518.

EXAMPLES Comparative Example 1

The wood stud wall system of Comparative Example 1 was evaluated in accordance with Section 1403.2 of the 2003 International Building Code, which mentions and incorporates ASTM E 331-00 entitled “Standard Test Method for Water Penetration of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static Air Pressure Difference.” Section 1403.2 of the 2003 International Building Code calls for a minimum differential pressure of 6.24 lbs/ft² (0.297 kN/m²). Since this minimum differential pressure correlates to about 50 miles per hour (mph), the testing was done using a 50 miles per hour wind speed.

The insulating sheathing comprised an extruded polystyrene foam flat board with polyethylene film facers. The overall size of the insulating sheathing was 48″ wide by 96″ high (48 inches by 96 inches) with a large sheet measuring 32″ wide by 96″ high and a small sheet measuring 16″ wide by 96″ high. The insulating sheathing had a total thickness of about ½″ (inch). Specifically, the insulating sheathing had a 0.42″ thick extruded polystyrene foam board adhesively bonded to a 0.002″ thick plastic facer on both sides. No reinforcement tapes or sealants were used.

The insulating sheathing was secured to a 2×4 Spruce-Pine-Fir wood buck measuring 48″×96″ with two vertical studs 16″ (inches) on center. The insulating sheathing was cut into two pieces—a large sheet measuring 32″ wide by 96″ high and a small sheet measuring 16″ wide by 96″ high. These two pieces were abutted together at one of the vertical studs. The insulating sheathing was secured to the wood buck using 1½″ plastic cap nails, 1″ from each corner and spaced 3″ apart, except at the vertical stud with no butt joint. The nails were spaced 6″ apart.

As a result of this testing under Section 1403.2, leakage occurred at the nail holes and sheathing edges in Comparative Example 1.

Comparative Example 2

The wood stud wall system of Comparative Example 2 was evaluated in accordance with Section 1403.2 of the 2003 International Building Code, which mentions and incorporates ASTM E 331-00 entitled “Standard Test Method for Water Penetration of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static Air Pressure Difference.” Section 1403.2 of the 2003 International Building Code calls for a minimum differential pressure of 6.24 lbs/ft² (0.297 kN/m²). Since this minimum differential pressure correlates to about 50 miles per hour (mph), the testing was done using a 50 miles per hour wind speed.

The insulating sheathing comprised an extruded polystyrene foam flat board with polyethylene film facers. The overall size of the insulating sheathing was 48″ wide by 96″ high (48 inches by 96 inches) with a large sheet measuring 32″ wide by 96″ high and a small sheet measuring 16″ wide by 96″ high. The insulating sheathing had a total thickness of about ½″ (inch). Specifically, the insulating sheathing had a 0.42″ thick extruded polystyrene foam board adhesively bonded to a 0.002″ thick plastic facer on both sides. No reinforcement tapes or sealants were used.

The insulating sheathing was secured to a 2×4 Spruce-Pine-Fir wood buck measuring 48″×96″ with two vertical studs 16″ (inches) on center. The insulating sheathing was cut into two pieces—a large sheet measuring 32″ wide by 96″ high and a small sheet measuring 16″ wide by 96″ high. These two pieces were abutted together at one of the vertical studs. The insulating sheathing was secured to the wood buck using 1½″ long, 1″ crown staples, 1″ from each corner and spaced 3″ apart, except at the vertical stud with no butt joint. The staples were spaced 6″ apart.

As a result of this testing under Section 1403.2, leakage occurred at the staple holes and sheathing edges in Comparative Example 2.

Inventive Example 1

The wood stud wall system of Inventive Example 1 was evaluated in accordance with Section 1403.2 of the 2003 International Building Code, which mentions and incorporates ASTM E 331-00 entitled “Standard Test Method for Water Penetration of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static Air Pressure Difference.” Section 1403.2 of the 2003 International Building Code calls for a minimum differential pressure of 6.24 lbs/ft² (0.297 kN/m²). Since this minimum differential pressure correlates to about 50 miles per hour (mph), the testing was done using a 50 miles per hour wind speed.

The structural insulating sheathing was an extruded polystyrene foam flat board with a layer of laminated paperboard therebetween. The paperboard comprised five identical layers of kraft paper that were laminated together. The overall size of the insulating sheathing was 48″ wide by 96″ high (48 inches by 96 inches) with a large sheet measuring 32″ wide by 96″ high and a small sheet measuring 16″ wide by 96″ high. The insulating sheathing had a total thickness of ½″ (inch). The insulating sheathing had two 0.20″ thick extruded polystyrene foam pieces adhesively bonded to respective sides of a 0.095″ thick paperboard panel. No reinforcement tapes or sealants were used.

The insulating sheathing was secured to a 2×4 Spruce-Pine-Fir wood buck measuring 48″×96″ (feet) with two vertical studs 16″ (inches) on center. The insulating sheathing was cut into two pieces—a large sheet measuring 32″ wide by 96″ high and a small sheet measuring 16″ wide by 96″ high. These two pieces were abutted together at one of the vertical studs. The insulating sheathing was secured to the wood buck using 1¾″ galvanized roofing nails, 1″ from each corner and spaced 3″ apart, except at the vertical stud with no butt joint. The nails were spaced 6″ apart.

As a result of this testing under Section 1403.2, no leakage occurred in Inventive Example 1.

Inventive Example 2

The wood stud wall system of Inventive Example 2 was evaluated in accordance with Section 1403.2 of the 2003 International Building Code, which mentions and incorporates ASTM E 331-00 entitled “Standard Test Method for Water Penetration of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static Air Pressure Difference.” Section 1403.2 of the 2003 International Building Code calls for a minimum differential pressure of 6.24 lbs/ft² (0.297 kN/m²). Since this minimum differential pressure correlates to about 50 miles per hour (mph), the testing was done using a 50 miles per hour wind speed.

The structural insulating sheathing was an extruded polystyrene foam flat board with a layer of laminated paperboard therebetween. The paperboard comprised five identical layers of kraft paper that were laminated together. The overall size of the insulating sheathing was 48″ wide by 96″ high (48 inches by 96 inches) with a large sheet measuring 32″ wide by 96″ high and a small sheet measuring 16″ wide by 96″ high. The insulating sheathing had a total thickness of ½″ (inch). The insulating sheathing had two 0.20″ thick extruded polystyrene foam pieces adhesively bonded to respective sides of a 0.115″ thick paperboard panel. No reinforcement tapes or sealants were used.

The insulating sheathing was secured to a 2×4 Spruce-Pine-Fir wood buck measuring 48″×96″ (feet) with two vertical studs 16″ (inches) on center. The insulating sheathing was cut into two pieces—a large sheet measuring 32″ wide by 96″ high and a small sheet measuring 16″ wide by 96″ high. These two pieces were abutted together at one of the vertical studs. The insulating sheathing was secured to the wood buck using 16 gauge, 1¾″ Senco staples with 7/16″ crown and a pneumatic fastening system. The staples were fastened at 3″ on center at all edges and 6″ on center in the field. Staples were installed at a depth where they were considered to be firmly resting on the paperboard layer of the sheathing upon insertion.

As a result of this testing under Section 1403.2, no leakage occurred in Inventive Example 2.

While the present invention has been described with reference to one or more particular embodiments, those skilled in the art will recognize that many changes may be made thereto without departing from the spirit and scope of the present invention. Each of these embodiments and obvious variations thereof is contemplated as falling within the spirit and scope of the claimed invention, which is set forth in the following claims. 

1. A method of forming a building wall system in the absence of building paper or housewrap, the method comprising the acts of: providing a generally flat structural insulating sheathing comprising at least a first layer, a second layer and a third layer, the first layer comprising an alkenyl aromatic polymer foam, the second layer comprising paperboard, and the third layer comprising an alkenyl aromatic polymer foam; providing a stud wall; and fastening the insulating sheathing to the stud wall to form the building wall system such that a seal is formed that inhibits water from penetrating therethrough, wherein the building wall system in the absence of building paper or housewrap passes the test requirements set forth in Section 1403.2 of the 2003 International Building Code.
 2. The method of claim 1, wherein the stud wall comprises wood.
 3. The method of claim 1, wherein the stud wall comprises metal.
 4. The method of claim 1, wherein the fastening of the insulating sheathing to the stud wall includes using a plurality of nails.
 5. The method of claim 4, wherein each of the plurality of nails includes a head, each of the head of the plurality of nails in its installed position is located near or at the face of the second layer.
 6. The method of claim 1, wherein the fastening of the insulating sheathing to the stud wall includes using an adhesive.
 7. The method of claim 1, wherein the fastening of the insulating sheathing to the stud wall includes using a plurality of staples.
 8. The method of claim 1, wherein the first and third layers comprise a polystyrene foam.
 9. The method of claim 8, wherein the first and third layers have a density of from about 1 to about 3 lbs/ft³.
 10. The method of claim 1, wherein the first and third layers are made of the same alkenyl aromatic polymer.
 11. The method of claim 1, wherein the thickness of each of the first and third layers is from about 0.1 to about 1 inch.
 12. The method of claim 1, wherein the paperboard is a paperboard laminate.
 13. The method of claim 1, wherein the thickness of the second layer is from about 0.05 to about 0.25 inch.
 14. The method of claim 1, wherein the insulating sheathing further includes a first laminated surface coating, the first laminated surface coating being attached to the first layer.
 15. The method of claim 14, wherein the insulating sheathing further includes a second laminated surface coating, the second laminated surface coating being attached to the third layer.
 16. The method of claim 1, wherein the building wall system is formed in the absence of tape and sealants.
 17. A method of forming a building wall system in the absence of building paper or housewrap, the method comprising the acts of: providing a generally flat structural insulating sheathing comprising at least a first foam layer, a second layer and a third foam layer, the first foam layer comprising a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof, the second layer comprising paperboard, and the third foam layer comprising a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof; providing a stud wall; and fastening the insulating sheathing to the stud wall to form the building wall system such that a seal is formed that inhibits water from penetrating therethrough, wherein the building wall system in the absence of building paper or housewrap passes the test requirements set forth in Section 1403.2 of the 2003 International Building Code.
 18. The method of claim 17, wherein the fastening of the insulating sheathing to the stud wall includes using a plurality of nails.
 19. The method of claim 18, wherein each of the plurality of nails includes a head, each of the head of the plurality of nails in its installed position is located near or at the face of the second layer.
 20. The method of claim 17, wherein the fastening of the insulating sheathing to the stud wall includes using an adhesive.
 21. The method of claim 17, wherein the fastening of the insulating sheathing to the stud wall includes using a plurality of staples.
 22. The method of claim 17, wherein the first and third foam layers are made of the same polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof.
 23. The method of claim 17, wherein the thickness of each of the first and third layers is from about 0.1 to about 1 inch.
 24. The method of claim 17, wherein the paperboard is a paperboard laminate.
 25. The method of claim 17, wherein the thickness of the second layer is from about 0.05 to about 0.25 inch.
 26. The method of claim 17, wherein the insulating sheathing further includes a first laminated surface coating, the first laminated surface coating being attached to the first layer.
 27. The method of claim 17, wherein the building wall system is formed in the absence of tape and sealants.
 28. A building wall system in the absence of building paper or housewrap, comprising: a stud wall; and a generally flat structural insulating sheathing comprising at least a first layer, a second layer, and a third layer, the first layer comprising an alkenyl aromatic polymer foam, the second layer comprising paperboard, and the third layer comprising an alkenyl aromatic polymer foam, the insulating sheathing being attached to the stud wall such that a seal is formed that inhibits water from penetrating therethrough, wherein the building wall system in the absence of building paper or housewrap passes the test requirements set forth in Section 1403.2 of the 2003 International Building Code.
 29. The building wall system of claim 28, wherein the first and third layers comprise a polystyrene foam.
 30. The building wall system of claim 28, wherein the first and third layers have a density of from about 1 to about 3 lbs/ft³.
 31. The building wall system of claim 28, wherein the thickness of each of the first and third layers is from about 0.1 to about 1 inch.
 32. The building wall system of claim 28, wherein the paperboard is a paperboard laminate.
 33. The building wall system of claim 28, wherein the thickness of the second layer is from about 0.05 to about 0.25 inch.
 34. A building wall system in the absence of building paper or housewrap, comprising: a stud wall; and a generally flat structural insulating sheathing comprising at least a first layer, a second layer, and a third layer, the first layer comprising a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof, the second layer comprising paperboard, and the third layer comprising a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof, the insulating sheathing being attached to the stud wall such that a seal is formed that inhibits water from penetrating therethrough, wherein the building wall system in the absence of building paper or housewrap passes the test requirements set forth in Section 1403.2 of the 2003 International Building Code.
 35. The building wall system of claim 34, wherein the first and third foam layers have a density of from about 1 to about 3 lbs/ft³.
 36. The building wall system of claim 34, wherein the thickness of each of the first and third foam layers is from about 0.1 to about 1 inch.
 37. The building wall system of claim 34, wherein the paperboard is a paperboard laminate.
 38. The building wall system of claim 34, wherein the thickness of the second layer is from about 0.05 to about 0.25 inch.
 39. A structural insulating sheathing adapted to be used in a building wall system, the insulating sheathing comprising a first layer, a second layer, and a third layer, the first layer comprising an alkenyl aromatic polymer foam, the second layer comprising paperboard, and the third layer comprising an alkenyl aromatic polymer foam, wherein the insulating sheathing has a flexural strength of at least 170 psi as measured in accordance with ASTM C 393, an R-value of at least 2.0 (ft²)(° F.)(hr)/(BTU) as measured in accordance with ASTM C
 518. 40. The sheathing of claim 39, wherein the insulating sheathing has a flexural strength of at least 225 psi as measured in accordance with ASTM C
 393. 41. The sheathing of claim 40, wherein the insulating sheathing has a flexural strength of at least 300 psi as measured in accordance with ASTM C
 393. 42. The sheathing of claim 39, wherein the insulating sheathing has an R-value of at least 2.5 as measured in accordance with ASTM C
 518. 43. The sheathing of claim 39, wherein the first and third layers have a density of from about 1 to about 3 lbs/ft³.
 44. The sheathing of claim 39, wherein the thickness of each of the first and third layers is from about 0.1 to about 1 inch.
 45. The sheathing of claim 39, wherein the paperboard is a paperboard laminate.
 46. The sheathing of claim 39, wherein the thickness of the second layer is from about 0.05 to about 0.25 inch.
 47. A structural insulating sheathing adapted to be used in a building wall system, the insulating sheathing comprising a first foam layer, a second layer, and a third foam layer, the first foam layer comprising a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof, the second layer comprising paperboard, and the third foam layer comprising a polyolefin, polyisocyanurate, polyurethane, polyester, or combinations thereof, wherein the insulating sheathing has a flexural strength of at least 170 psi as measured in accordance with ASTM C 393, an R-value of at least 2.0 (ft²)(° F.)(hr)/(BTU) as measured in accordance with ASTM C
 518. 48. The sheathing of claim 47, wherein the insulating sheathing has a flexural strength of at least 225 psi as measured in accordance with ASTM C
 393. 49. The sheathing of claim 47, wherein the insulating sheathing has a flexural strength of at least 300 psi as measured in accordance with ASTM C
 393. 50. The sheathing of claim 47, wherein the insulating sheathing has an R-value of at least 2.5 as measured in accordance with ASTM C
 518. 51. The sheathing of claim 47, wherein the first and third foam layers have a density of from about 1 to about 3 lbs/ft³.
 52. The sheathing of claim 47, wherein the thickness of each of the first and third foam layers is from about 0.1 to about 1 inch.
 53. The sheathing of claim 47, wherein the paperboard is a paperboard laminate.
 54. The sheathing of claim 47, wherein the thickness of the second layer is from about 0.05 to about 0.25 inch. 